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            <div><h4 class="title">
                <a name="asio.reference.async_connect.overload5"></a><a class="link" href="overload5.html"
                                                                        title="async_connect (5 of 6 overloads)">async_connect
                (5 of 6 overloads)</a>
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    <p>
        (Deprecated: Use range overload.) Asynchronously establishes a socket connection
        by trying each endpoint in a sequence.
    </p>
    <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <a class="link" href="../Protocol.html"
                                             title="Protocol requirements">Protocol</a><span class="special">,</span>
    <span class="keyword">typename</span> <a class="link" href="../Executor1.html" title="Executor requirements">Executor</a><span
                class="special">,</span>
    <span class="keyword">typename</span> <span class="identifier">Iterator</span><span class="special">,</span>
    <span class="keyword">typename</span> <a class="link" href="../ConnectCondition.html"
                                             title="Connect condition requirements">ConnectCondition</a><span
                class="special">,</span>
    <span class="keyword">typename</span> <a class="link" href="../IteratorConnectToken.html"
                                             title="Iterator connect token requirements">IteratorConnectToken</a> <span
                class="special">=</span> <a class="link"
                                            href="../asynchronous_operations.html#asio.reference.asynchronous_operations.default_completion_tokens"><span
                class="emphasis"><em>DEFAULT</em></span></a><span class="special">&gt;</span>
<a class="link"
   href="../asynchronous_operations.html#asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type"><span
        class="emphasis"><em>DEDUCED</em></span></a> <span class="identifier">async_connect</span><span class="special">(</span>
    <span class="identifier">basic_socket</span><span class="special">&lt;</span> <span
                class="identifier">Protocol</span><span class="special">,</span> <span
                class="identifier">Executor</span> <span class="special">&gt;</span> <span class="special">&amp;</span> <span
                class="identifier">s</span><span class="special">,</span>
    <span class="identifier">Iterator</span> <span class="identifier">begin</span><span class="special">,</span>
    <span class="identifier">ConnectCondition</span> <span class="identifier">connect_condition</span><span
                class="special">,</span>
    <span class="identifier">IteratorConnectToken</span> <span class="special">&amp;&amp;</span> <span
                class="identifier">token</span> <span class="special">=</span> <a class="link"
                                                                                  href="../asynchronous_operations.html#asio.reference.asynchronous_operations.default_completion_tokens"><span
                class="emphasis"><em>DEFAULT</em></span></a><span class="special">,</span>
    <span class="keyword">typename</span> <span class="identifier">constraint</span><span
                class="special">&lt;!</span><span class="identifier">is_endpoint_sequence</span><span class="special">&lt;</span> <span
                class="identifier">Iterator</span> <span class="special">&gt;::</span><span
                class="identifier">value</span> <span class="special">&gt;::</span><span class="identifier">type</span>  <span
                class="special">=</span> <span class="number">0</span><span class="special">);</span>
</pre>
    <p>
        This function attempts to connect a socket to one of a sequence of endpoints.
        It does this by repeated calls to the socket's <code class="computeroutput"><span class="identifier">async_connect</span></code>
        member function, once for each endpoint in the sequence, until a connection
        is successfully established. It is an initiating function for an <a class="link"
                                                                            href="../../overview/model/async_ops.html"
                                                                            title="Asynchronous Operations">asynchronous
        operation</a>,
        and always returns immediately.
    </p>
    <h6>
        <a name="asio.reference.async_connect.overload5.h0"></a>
        <span><a name="asio.reference.async_connect.overload5.parameters"></a></span><a class="link"
                                                                                        href="overload5.html#asio.reference.async_connect.overload5.parameters">Parameters</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">s</span></dt>
            <dd><p>
                The socket to be connected. If the socket is already open, it will
                be closed.
            </p></dd>
            <dt><span class="term">begin</span></dt>
            <dd><p>
                An iterator pointing to the start of a sequence of endpoints.
            </p></dd>
            <dt><span class="term">connect_condition</span></dt>
            <dd>
                <p>
                    A function object that is called prior to each connection attempt.
                    The signature of the function object must be:
                </p>
                <pre class="programlisting"><span class="keyword">bool</span> <span
                        class="identifier">connect_condition</span><span class="special">(</span>
    <span class="keyword">const</span> <span class="identifier">asio</span><span class="special">::</span><span
                            class="identifier">error_code</span><span class="special">&amp;</span> <span
                            class="identifier">ec</span><span class="special">,</span>
    <span class="keyword">const</span> <span class="keyword">typename</span> <span
                            class="identifier">Protocol</span><span class="special">::</span><span class="identifier">endpoint</span><span
                            class="special">&amp;</span> <span class="identifier">next</span><span
                            class="special">);</span>
</pre>
                <p>
                    The <code class="computeroutput"><span class="identifier">ec</span></code> parameter
                    contains the result from the most recent connect operation. Before
                    the first connection attempt, <code class="computeroutput"><span class="identifier">ec</span></code>
                    is always set to indicate success. The <code class="computeroutput"><span
                        class="identifier">next</span></code>
                    parameter is the next endpoint to be tried. The function object should
                    return true if the next endpoint should be tried, and false if it
                    should be skipped.
                </p>
            </dd>
            <dt><span class="term">token</span></dt>
            <dd>
                <p>
                    The <a class="link" href="../../overview/model/completion_tokens.html" title="Completion Tokens">completion
                    token</a> that will be used to produce a completion handler, which
                    will be called when the connect completes. Potential completion tokens
                    include <a class="link" href="../use_future.html" title="use_future"><code
                        class="computeroutput"><span class="identifier">use_future</span></code></a>,
                    <a class="link" href="../use_awaitable.html" title="use_awaitable"><code
                            class="computeroutput"><span class="identifier">use_awaitable</span></code></a>,
                    <a class="link" href="../yield_context.html" title="yield_context"><code
                            class="computeroutput"><span class="identifier">yield_context</span></code></a>,
                    or a function object with the correct completion signature. The function
                    signature of the completion handler must be:
                </p>
                <pre class="programlisting"><span class="keyword">void</span> <span
                        class="identifier">handler</span><span class="special">(</span>
  <span class="comment">// Result of operation. if the sequence is empty, set to</span>
  <span class="comment">// asio::error::not_found. Otherwise, contains the</span>
  <span class="comment">// error from the last connection attempt.</span>
  <span class="keyword">const</span> <span class="identifier">asio</span><span class="special">::</span><span
                            class="identifier">error_code</span><span class="special">&amp;</span> <span
                            class="identifier">error</span><span class="special">,</span>

  <span class="comment">// On success, an iterator denoting the successfully</span>
  <span class="comment">// connected endpoint. Otherwise, the end iterator.</span>
  <span class="identifier">Iterator</span> <span class="identifier">iterator</span>
<span class="special">);</span>
</pre>
                <p>
                    Regardless of whether the asynchronous operation completes immediately
                    or not, the completion handler will not be invoked from within this
                    function. On immediate completion, invocation of the handler will
                    be performed in a manner equivalent to using <a class="link" href="../post.html" title="post"><code
                        class="computeroutput"><span class="identifier">post</span></code></a>.
                </p>
            </dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.async_connect.overload5.h1"></a>
        <span><a name="asio.reference.async_connect.overload5.completion_signature"></a></span><a class="link"
                                                                                                  href="overload5.html#asio.reference.async_connect.overload5.completion_signature">Completion
        Signature</a>
    </h6>
    <pre class="programlisting"><span class="keyword">void</span><span class="special">(</span><span class="identifier">asio</span><span
            class="special">::</span><span class="identifier">error_code</span><span class="special">,</span> <span
            class="identifier">Iterator</span><span class="special">)</span>
</pre>
    <h6>
        <a name="asio.reference.async_connect.overload5.h2"></a>
        <span><a name="asio.reference.async_connect.overload5.remarks"></a></span><a class="link"
                                                                                     href="overload5.html#asio.reference.async_connect.overload5.remarks">Remarks</a>
    </h6>
    <p>
        This overload assumes that a default constructed object of type <code class="computeroutput"><span
            class="identifier">Iterator</span></code> represents the end of the sequence.
        This is a valid assumption for iterator types such as <code class="computeroutput"><span
            class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span
            class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span
            class="identifier">resolver</span><span class="special">::</span><span
            class="identifier">iterator</span></code>.
    </p>
    <h6>
        <a name="asio.reference.async_connect.overload5.h3"></a>
        <span><a name="asio.reference.async_connect.overload5.per_operation_cancellation"></a></span><a class="link"
                                                                                                        href="overload5.html#asio.reference.async_connect.overload5.per_operation_cancellation">Per-Operation
        Cancellation</a>
    </h6>
    <p>
        This asynchronous operation supports cancellation for the following <a class="link"
                                                                               href="../cancellation_type.html"
                                                                               title="cancellation_type"><code
            class="computeroutput"><span class="identifier">cancellation_type</span></code></a>
        values:
    </p>
    <div class="itemizedlist">
        <ul class="itemizedlist" type="disc">
            <li class="listitem">
                <code class="computeroutput"><span class="identifier">cancellation_type</span><span
                        class="special">::</span><span class="identifier">terminal</span></code>
            </li>
            <li class="listitem">
                <code class="computeroutput"><span class="identifier">cancellation_type</span><span
                        class="special">::</span><span class="identifier">partial</span></code>
            </li>
        </ul>
    </div>
    <p>
        if they are also supported by the socket's <code class="computeroutput"><span
            class="identifier">async_connect</span></code>
        operation.
    </p>
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                Distributed under the Boost Software License, Version 1.0. (See accompanying
                file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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